More work on Jpeg and Png.

Jpeg saving is almost working, then need to move to decoding.
juliusfriedman · Oct 20, 2024 · cbf2608 · cbf2608
1 parent 33625ce
commit cbf2608
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Showing 6 changed files with 58 additions and 20 deletions.
diff --git a/Codecs/Image/Image.cs b/Codecs/Image/Image.cs
@@ -1,14 +1,12 @@
-using Codecs.Image;
-using Media.Codec;
+using Media.Codec;
+using Media.Codec.Interfaces;
 using Media.Codecs.Image;
 using Media.Common;
 using System;
 using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using System.Numerics;
-using System.Text;
-using static System.Runtime.InteropServices.JavaScript.JSType;
 
 namespace Media.Codecs.Image
 {
@@ -103,8 +101,8 @@ public Image(ImageFormat format, int width, int height, byte[] data)
             Height = height;
         }
 
-        public Image(ImageFormat format, int width, int height, MemorySegment data)
-            : base(format, data)
+        public Image(ImageFormat format, int width, int height, MemorySegment data, ICodec codec = null)
+            : base(format, data, codec)
         {
             Width = width;
 
@@ -115,6 +113,8 @@ public Image(ImageFormat format, int width, int height, MemorySegment data)
 
         #region Properties
 
+        public double AspectRatio => Width / Height;
+
         //Should be Vector<byte>?
 
         //Assumes component order

diff --git a/Codecs/Image/Jpeg/JpegImage.cs b/Codecs/Image/Jpeg/JpegImage.cs
@@ -4,6 +4,7 @@
 using Media.Codecs.Image;
 using Media.Common;
 using System.Collections.Generic;
+using System.Linq;
 
 namespace Media.Codec.Jpeg;
 
@@ -17,8 +18,13 @@ public JpegImage(ImageFormat imageFormat, int width, int height)
     {
     }
 
+    public JpegImage(ImageFormat imageFormat, int width, int height, MemorySegment data)
+    : base(imageFormat, width, height, new JpegCodec())
+    {
+    }
+
     private JpegImage(ImageFormat imageFormat, int width, int height, MemorySegment data, bool progressive, List<Marker> markers)
-        : base(imageFormat, width, height, data)
+        : this(imageFormat, width, height, data)
     {
         Progressive = progressive;
         Markers = markers;
@@ -30,8 +36,8 @@ public static JpegImage FromStream(Stream stream)
 
         // Read the SOF0 (Start of Frame) marker
         int width = 0, height = 0;
-        ImageFormat? imageFormat = default;
-        MemorySegment? dataSegment = default;
+        ImageFormat imageFormat = default;
+        MemorySegment dataSegment = default;
         bool progressive = false;
         List<Marker> markers = new List<Marker>();
         foreach (var marker in markerReader.ReadMarkers())
@@ -60,7 +66,9 @@ public static JpegImage FromStream(Stream stream)
                     var samplingFactors = marker.Data[offset++];
                     widths[componentIndex] = samplingFactors & 0x0F;
                     heights[componentIndex] = samplingFactors >> 4;
-                    var quantizationTableNumber = marker.Data[offset++];
+
+                    //TODO CMYK image throws this off?
+                    //var quantizationTableNumber = marker.Data[offset++];
 
                     var mediaComponent = new MediaComponent(componentId, bitDepth);
 
@@ -78,7 +86,7 @@ public static JpegImage FromStream(Stream stream)
                 dataSegment = marker.Data;
                 break;
             }
-            else
+            else if (marker.FunctionCode != Jpeg.Markers.StartOfInformation)
             {
                 markers.Add(marker);
             }
@@ -98,7 +106,15 @@ public void Save(Stream stream)
 
         if (Markers != null)
         {
-            foreach (var marker in Markers)
+            foreach (var marker in Markers.Where(marker => marker.FunctionCode == Jpeg.Markers.TextComment))
+            {
+                WriteMarker(stream, marker.FunctionCode, (s) => s.Write(marker.Data.Array, marker.Data.Offset, marker.Data.Count));
+            }
+        }
+
+        if (Markers != null)
+        {
+            foreach (var marker in Markers.Where(marker => marker.FunctionCode == Jpeg.Markers.QuantizationTable))
             {
                 WriteMarker(stream, marker.FunctionCode, (s) => s.Write(marker.Data.Array, marker.Data.Offset, marker.Data.Count));
             }
@@ -107,6 +123,14 @@ public void Save(Stream stream)
         // Write the SOF0 marker
         WriteMarker(stream, Progressive ? Jpeg.Markers.StartOfProgressiveFrame : Jpeg.Markers.StartOfBaselineFrame, WriteSOF0Marker);
 
+        if (Markers != null)
+        {
+            foreach (var marker in Markers.Where(marker => marker.FunctionCode == Jpeg.Markers.HuffmanTable))
+            {
+                WriteMarker(stream, marker.FunctionCode, (s) => s.Write(marker.Data.Array, marker.Data.Offset, marker.Data.Count));
+            }
+        }
+
         // Write the SOS marker
         WriteMarker(stream, Jpeg.Markers.StartOfScan, WriteSOSMarker);
 
@@ -163,7 +187,7 @@ private void WriteMarker(Stream writer, byte functionCode, Action<Stream> writeM
         {
             writeMarkerData(ms);
             ms.TryGetBuffer(out var markerData);
-            Marker marker = new Marker(functionCode, markerData.Count + Binary.BytesPerShort);
+            Marker marker = new Marker(functionCode, markerData.Count > 0 ? markerData.Count + Binary.BytesPerShort : 0);
             markerData.CopyTo(marker.Data.Array, marker.Data.Offset);
             writer.Write(marker.Array, marker.Offset, marker.Count);
         }

diff --git a/Codecs/Image/Jpeg/JpegUnitTests.cs b/Codecs/Image/Jpeg/JpegUnitTests.cs
@@ -212,8 +212,19 @@ public static void TestLoad()
 
             var saveFileName = Path.Combine(outputDir, Path.GetFileName(filePath));
 
-            using var outputNew = new FileStream(saveFileName, FileMode.OpenOrCreate, FileAccess.Write);
-            jpgImage.Save(outputNew);
+            using (var outputNew = new FileStream(saveFileName, FileMode.OpenOrCreate, FileAccess.Write))
+            {
+                jpgImage.Save(outputNew);
+            }
+
+            using var inputNew = new FileStream(saveFileName, FileMode.OpenOrCreate, FileAccess.Read);
+
+            using var newJpgImage = JpegImage.FromStream(inputNew);
+
+            if (newJpgImage.Width != jpgImage.Width ||
+                newJpgImage.Height != jpgImage.Height ||
+                newJpgImage.Progressive != jpgImage.Progressive)
+                    throw new InvalidDataException();
         }
     }
 }
diff --git a/Codecs/Image/Jpeg/Marker.cs b/Codecs/Image/Jpeg/Marker.cs
@@ -25,13 +25,14 @@ public int Length
 
     public int DataSize => Binary.Max(0, Length - 2);
 
-    public MemorySegment Data => new MemorySegment(Array, Offset + Binary.BytesPerInteger, DataSize);
+    public MemorySegment Data => DataSize > 0 ? new MemorySegment(Array, Offset + Binary.BytesPerInteger, DataSize) : Common.MemorySegment.Empty;
 
     public Marker(byte functionCode, int size)
-        : base(new byte[size + Binary.BytesPerInteger])
+        : base(new byte[size > 0 ? size + Binary.BytesPerInteger : size + Binary.BytesPerShort])
     {
         Prefix = Markers.Prefix;
         FunctionCode = functionCode;
-        Length = size;
+        if (size > 0)
+            Length = size;
     }
 }
diff --git a/Codecs/Image/Png/Codec.Png/ChunkHeader.cs b/Codecs/Image/Png/Codec.Png/ChunkHeader.cs
@@ -23,6 +23,8 @@ public uint Length
         set => Binary.Write32(Array, Offset, Binary.IsLittleEndian, value);
     }
 
+    public int TotalLength => (int)(Length + Binary.BytesPerInteger);
+
     public uint Type
     {
         get => Binary.ReadU32(Array, Offset + Binary.BytesPerInteger, Binary.IsLittleEndian);

diff --git a/Codecs/Image/Png/Codec.Png/PngImage.cs b/Codecs/Image/Png/Codec.Png/PngImage.cs
@@ -47,7 +47,7 @@ public PngImage(ImageFormat imageFormat, int width, int height)
     }
 
     private PngImage(ImageFormat imageFormat, int width, int height, MemorySegment data)
-        : base(imageFormat, width, height, data)
+        : base(imageFormat, width, height, data, new PngCodec())
     {
     }
 
@@ -129,7 +129,7 @@ public static PngImage FromStream(Stream stream)
             else
             {
                 // Skip the chunk data and CRC
-                stream.Seek(chunkHeader.Length + Binary.BytesPerInteger, SeekOrigin.Current);
+                stream.Seek(chunkHeader.TotalLength, SeekOrigin.Current);
             }
         }